This invention relates generally to feed tube protectors for limiting the access to wide mouth feed tubes of food processors and, more particularly, to apparatus for preventing removal of hingedly mounted feed tube protectors during operation of the food processors.
Food processors are a well known convenience for preparing food by slicing, grating, shredding or similar food processing operations. A conventional form of food processor includes a working bowl having a motor driven shaft projecting upwardly in the center of the bowl. A variety of food processing tools are coupled to the shaft and rotated to perform a corresponding variety of food processing operations as required by the operator of the food processor.
A detachable bowl cover is secured to the working bowl during operation a feed tube for introducing food items to be processed through the bowl cover into the bowl. Foods to be processed are placed into the feed tube and then pushed through the tube into engagement with a processing tool by means of a food pusher which is formed to be slidingly inserted into the feed tube.
Frequently, feed tubes for food processors are relatively tall, narrow structures which prevent an adult from inadvertently inserting a normal hand through the feed tube and into contact with a rotating tool located in the upper portion of the working bowl. A safety interlock is provided to prevent the food processor from operating until the bowl cover is firmly secured to the bowl in its proper operating position.
The interlock is performed by a projection or cam formed on the bowl cover which causes the closing of a switch carried by the base of the food processor only when the bowl cover is properly secured to the bowl. Various designs provide for the operation of the switch directly or through intermediate mechanical linkages. Alternately, the switch may be magnetically activated by properly positioning and securing the bowl cover.
Unfortunately, the tall, narrow feed tubes also limit the size, shape and single load quantity of a food item which can be processed. To process larger sizes, larger single load quantities and variously shaped food items, for example, to slice relatively large size tomatoes or to lengthwise slice carrots, cucumbers or the like, enlarged feed tubes have been provided. Of course, safety considerations still apply and, hence, alternate safety or protection arrangements must be provided for such enlarged feed tubes.
One protector for an enlarged feed tube is disclosed in Williams, U.S. Pat. No. 4,226,373. The Williams feed tube protector comprises a sleeve which is sized and shaped to be slid over the feed tube of the food processor with the sleeve including an actuator for enabling motor operation only when the sleeve is properly positioned over the feed tube.
A telescoping food pusher which is sized to be received within the feed tube is captively connected to the sleeve such that the food pusher may be moved up and down within the feed tube, but may not be removed from the sleeve. In Williams, the captured food pusher blocks access through the enlarged feed tube when the sleeve is properly positioned over the feed tube to enable operation of the food processor.
Another approach to protection of an enlarged feed tube is disclosed by Behringer et al. in European Patent Publication No. 0084745. A cylindrical hopper nearly equal in diameter to the working bowl forms a combination bowl cover and enlarged feed tube, and is secured to the working bowl. The enlarged cylindrical feed tube includes a radially extending partition to prevent food from being circulated by the processing tool which is to work upon it. The enlarged cylindrical feed tube is closed by a feed tube cover which must be properly positioned over the feed tube before the food processor motor may be operated. An opening in the cover admits a food pusher including a pusher plate which is slotted to receive the partition.
While both Williams and Behringer et al. protect enlarged feed tube openings, the associated protection devices must be completely detached from the food processor and set aside while food to be processed is loaded into the enlarged feed tubes. The protection devices must then be replaced before the food processor can be operated. Removal and replacement of the protective devices is inconvenient and the protective devices, once removed, occupy counter space and may interface with activities associated with operation of the food processor. Further, since the protective devices are completely removed and set aside from the food processor, they may be temporarily mislaid leading to delays and frustration in use of the food processor.